So I'm looking into the possibility of making a wireless charging solution on my own. I have lots of wireless chargers at home, work, in the car, and I would really benefit from getting wireless charging working.
I took a USB Qi charging coil and soldered wires, which I then attached (well, just touched ) to either end of the magnetic connector, and it worked.
The difficulty I'm facing is, how can I keep these wires touching the magnetic charging port semi-permanently without doing anything dangerous like attempting to solder it directly.
So I'm wondering if anyone has any neat ideas of how I might rig this up. Any ideas would help a lot! If I come up with something good, I'll make a guide so others can do it.
You could try to get someone to 3D print a side piece similar to the one on the Z3 wireless charging case from sony: http://www.sonymobile.com/us/products/accessories/wireless-charging-cover-wcr14/
Have them leave chambers to run the wire through.
JCBomb said:
You could try to get someone to 3D print a side piece similar to the one on the Z3 wireless charging case from sony: http://www.sonymobile.com/us/products/accessories/wireless-charging-cover-wcr14/
Have them leave chambers to run the wire through.
Click to expand...
Click to collapse
I've been thinking about making my own wireless charging case similar to the sony branded case but using high quality leather, and an oem qi charging circuit with a 3d printed base clip with the circuit connectors integrated into the clip, just to ensure constant connectivity.
just looking into prices for scrap leather now.
duraaraa said:
So I'm looking into the possibility of making a wireless charging solution on my own. I have lots of wireless chargers at home, work, in the car, and I would really benefit from getting wireless charging working.
I took a USB Qi charging coil and soldered wires, which I then attached (well, just touched ) to either end of the magnetic connector, and it worked.
The difficulty I'm facing is, how can I keep these wires touching the magnetic charging port semi-permanently without doing anything dangerous like attempting to solder it directly.
So I'm wondering if anyone has any neat ideas of how I might rig this up. Any ideas would help a lot! If I come up with something good, I'll make a guide so others can do it.
Click to expand...
Click to collapse
Have you tried tape? It would be covered up by your case anyway, right?
PuffDaddy_d said:
Have you tried tape? It would be covered up by your case anyway, right?
Click to expand...
Click to collapse
I've thought of tape but I've yet to figure out a way to tape it where it will definitely stay in place.
I might be able to get a case that would cover it, but my current cases have holes so that magnetic chargers could be plugged in.
I've decided to try using copper tape to connect a Qi coil to the magnetic dock port. I'll see how it goes. Hopefully it will be as easy as I'm hoping it will be.
So I finally managed to make it work. Unfortunately, I had to solder.
I gave up with trying to line things up just right and keep it in place, so I just soldered a Qi receiver to the magnetic charging port, wrapped it around to the back of the phone, and fit in a case. It charges wirelessly now, so I'm happy. Unfortunately, I don't know if I'll ever be able to clean it up in the future if I want to sell the phone. But to me, wireless charging was super important. I was also able to continue using my Z1C battery case which uses the magnetic port, so I'm pretty happy with the end result.
Pics?
it's ugly, but I'll put up pics when I get a chance.
Pictures as promised. I had been concerned adding this might block NFC, but NFC works just fine. Obviously, magnetic charging cables don't work (but a Z1C charging case I have does.)
It adds some thickness behind it so the case doesn't fit quite perfectly, but well enough to stay on. I didn't have thinner cables, but having some might have been able to decrease the thickness. Also, I'm not necessarily good at soldering, so I just did what I could.
But I can charge it on my bedside table and in my iOttie Qi dock in my car, so I'm cool with it.
hmm not pretty, but i guess it works. how is the charging speed?
you should be able to clean it up fine if you use some solder wick.
Awesome job!
Can you please give us a link for the receiver?
All I can find are with usb
ugly doesn't even start describing it... seriously, you ruined that phone. You could've cannibalized a 3rd party docking station instead
duraaraa,
Thanks for blazing this trail for us, mighty brave to solder to your phone like that! Now that you've had this set up for a few weeks, is it holding up ok? I'd just about give my left nut for an actual phone case that simply has a wireless receiver built in and taps into the magnetic charger pins, but I doubt anyone will ever make one since (I believe) the Z3C is discontinued. I mean, they make those giant external battery packs for the Z3C that use the pins, so why not a qi-compatible one??? Anyway, no way I'm soldering to my pins so I'm basically trying to mold a connector out of epoxy that I can squeeze between the side of the case and the pins. (Basically I pushed one of my magnetic cable connectors into a clay bar and filled w/epoxy.) It's still drying so I have no idea if it's feasible at all, but wanted to pop in and say thanks for the inspiration.
mralexsays said:
duraaraa,
Thanks for blazing this trail for us, mighty brave to solder to your phone like that! Now that you've had this set up for a few weeks, is it holding up ok? I'd just about give my left nut for an actual phone case that simply has a wireless receiver built in and taps into the magnetic charger pins, but I doubt anyone will ever make one since (I believe) the Z3C is discontinued. I mean, they make those giant external battery packs for the Z3C that use the pins, so why not a qi-compatible one??? Anyway, no way I'm soldering to my pins so I'm basically trying to mold a connector out of epoxy that I can squeeze between the side of the case and the pins. (Basically I pushed one of my magnetic cable connectors into a clay bar and filled w/epoxy.) It's still drying so I have no idea if it's feasible at all, but wanted to pop in and say thanks for the inspiration.
Click to expand...
Click to collapse
hows your build coming along mate I'd love to see how it looks.
kstanley7 said:
hows your build coming along mate I'd love to see how it looks.
Click to expand...
Click to collapse
Not good I'm afraid my friend... My first attempt (trying to mold a connector out of epoxy using a clay mold) failed, the thing came out looking like a chewed up piece of gum and just wouldn't work. My next attempt involved slicing up a couple of cheap magnetic adapters and cables to try to trim down the connectors to something reasonably sized, but they become really brittle when you cut them that thin... Unfortunately, I think it'd take someone with some type of plastic molding equipment or maybe a 3d printer (that is capable of making really small, fine-detail parts) to make this thing. I'm still disappointed that Sony makes a wireless case for the Z3, but not the Z3C, but I've also come to realize that the Z3C has such good battery life that maybe I don't really need such a case. (I come from a long line of Nexus, HTC, and Samsung devices so I've become somewhat of a charging addict!)
tl;dr: Just enjoy the Z3C and use the handy magnetic dock for overnight charging.
just looking at the magnetic connectors on the z3c I think there might be a way but it'll add a couple more mm to the height, would need to get someone with a 3d printer, but if the wallet is made of leather and is inserted underneath, with the qi wireless pad, and two wires made into connection terminals which would then clip onto the phone so a solid connection is made between those terminals.
Just to answer some questions, it's held up. I think it's fine -- anyone desperate for Qi should just bite the bullet and solder. Charging speed is similar to really any other Qi-charged device.
apis10 said:
Awesome job!
Can you please give us a link for the receiver?
All I can find are with usb
Click to expand...
Click to collapse
Sorry my response is so late!
It's the USB type. I un-soldered the USB ribbon and soldered a wire for the two connections.
So you would want to buy the USB version, I think.
Look into copper tape. I attempted this a little while back but I think my charging pad wasn't powerful enough. What charging pad are you using?
Related
I decided to post a new thread as most of them out there are for Galaxy Note II or Galaxy i9305
Before you start doing anything I'd suggest reading all these threads so you decide what's best for you.
http://forum.xda-developers.com/showthread.php?t=2096585
This one,although for Galaxy Note, IS REALLY GOOD. THANKS to "Ryan_G" for making such detailed explanation and pics, it helped me a lot!
http://forum.xda-developers.com/showthread.php?t=1951493
Thanks to android94301 for this one:
http://forum.xda-developers.com/showthread.php?t=1877191
thanks to Richard Searley who explains which pin is positive and negative.
http://www.youtube.com/watch?v=uAqP3T_Mbzg
thanks to "qianqinde" for showing how to remove the parts from the Palm cover.
http://youtu.be/0ga4N_Ih9GE?t=4m21s
The Parts I used:
1.Palm Touchstone Charging Dock-£4.99Amazon UK
2.Original Palm Touchstone Back Cover-£3.49Ebay UK
3.Soldering Iron + solder
4.Clear tape,because it's very thin. black electrical tape is thicker and want to make the slight bulge as smaller as possible. you will see on one of the pics i used electrical tape, but I removed it and used clear tape
5.Wires from old not Genuine iPad cable; because the wires are very thin.
Palm Pixi Cover-£3.99Ebay UK If you buy one of those,as far as I know positive and negative are not reversed (CHECK for yourselves before doing anything) as on Palm Pre cover!
Genuine Palm charger-£3.99Ebay UKI got this charger, because I needed a one anyway
Chargers I can confirm they work with the Palm charging dock: Galaxy S3(5v-1A)##Nexus 7 (2A)## old HTC Desire Charger (5v,1A)## If your phone keeps vibrating and the window that says charging keeps popping up over and over again, your charger is not supplying sufficient power. My Motorola charger(800mA) did that.
Good soldering skills are needed to perform the mod. I guess you wouldn't wanna melt the plastic on the phone so practice before you attempt this. Twist the wires to the desired shape first and then solder. This way you will prevent breaking off the pins from the motherboard
When you see the pics, you will notice I barery used any solder, this is, because you really don't need much as it catches really easy. It should't be a problem since there are no moving parts there to force the wires to fell off.
Decided to stick everything to the battery,because I rarely remove it.
You will notice on the pics I've put the wires along the of the battery as there is enough space for them to go in nicely
When you solder avoid pulling the wires too much so you dont damage the pins on the Phone's motherboard.
Put a piece of card board on the battery when you solder so you don't damage it.
If you have very thin wires don't hold the soldering iron for too long because you will melt the insulation around the wire. you could blow a few time so it cools down faster.
Hi,
I recently bought a qi wireless charger because my charger port of the phone broke and it's too expensive to fix.
Anyways, yesterday I left it for 2 hours the % went from 49 to 90 which I was quite happy with but I let it charge over night and it only went from 34% to 50%.
I am rooted and on AOSP.
I check the wireless current and sometimes as soon as I put it on the pad it's 1000ma but then it keeps dropping quick to 100ma. The pad as an output of 1000ma.
Csn someone tell me how to fix the slow charge. Thanks
Sent from my GT-I9300 using XDA Premium 4 mobile app
you're probalby not lining it up properly. that happens when you've misaligned the pad to the charger. find the sweet spot and just remember to place your phone there the same way.
if you're handy,you can probably also come up with a cradle of some sort so the phone falls right in place everytime.
mputtr said:
you're probalby not lining it up properly. that happens when you've misaligned the pad to the charger. find the sweet spot and just remember to place your phone there the same way.
if you're handy,you can probably also come up with a cradle of some sort so the phone falls right in place everytime.
Click to expand...
Click to collapse
I placed mini rare earth magnets under the phone's back plate, just 2 on the top area, and then 2 on the Qi wireless charger so the phone aligns perfectly with the charger, and gets the best charge it can get.. Also I opened up all my Qi Chargers and used my Dremel to remove all the extra plastic, as much as I could to remove any kind of resistance or space between the Tx Coil and the Rx Coil.. I tested the best place they could be aligned with a Multi Meter, and then added magnets.. Works like a charm.. Its a pain in the ass, but mine works out pretty well. I didn't place the magnets on the inside, I placed them on the outside of the charger.. Works well
http://www.ebay.com/itm/271329239542?_trksid=p2059210.m2749.l2649&ssPageName=STRK:MEBIDX:IT
thats what I purchased..
uh wow... that's seriously overkill but sure.. you can do that..
although i wonder if putting magnets that strong in your phone will mess with your gps and magnetometer.
i would say a small plastic cradle or creating little edges on the transmitter so the phone just physically falls in would be an easier and safer alternative that using a dremel on your receiver.
mputtr said:
uh wow... that's seriously overkill but sure.. you can do that..
although i wonder if putting magnets that strong in your phone will mess with your gps and magnetometer.
i would say a small plastic cradle or creating little edges on the transmitter so the phone just physically falls in would be an easier and safer alternative that using a dremel on your receiver.
Click to expand...
Click to collapse
I would of thought the same thing, but it has given me zero problems when the magnets are set up top.. HOWEVER, when I tried to place 2 near the bottom, it caused all kinds of problems with USB charging and my phone locked up a few times... I'm glad the damage wasn't permanent.. I used my Hotglue gun to hold them into place, the magnetic field caused a short in the Gluegun and it EXPLODED in my hand.. I was lucky enough to drop it right when I heard the sizzle and BANG.. So when playing with strong magnets.. Be careful.
Edit: I also have an external case with the same type magnets, and even with the case on, it doesn't give me any issues, at least any I'm aware of.. I made a magnetic mount on my desktop pc, just for kicks.. But since the case is metal, I can't put a Qi charging coil on it.. Now that would be neat..
yeah.. that's dangerous in general. I honestly would not recommend anyone to do what you did considering you almost ended up with stuff blowing up un your hands.
Sent from my GT-I9300 using XDA Free mobile app
The idea behind Qi is simple: all devices with the Qi logo will work with all Qi chargers. That’s it. No need for separate chargers, no need for cables, and no need for adapters when traveling. Qi is a global standard – this means that your device can be charged wirelessly wherever you are.
As we all know, the new Zenfone 2 is missing wireless charging capabilities, however there are multiple solutions to enable wireless charging on basically any phone.
Example is http://www.amazon.com/BEZALEL®-Wire..._1_4?s=wireless&ie=UTF8&qid=1432149451&sr=1-4
It is a cover with a Qi receiver built in, which connects to the charging port and it also provides an independent micro usb port as a part of the case.
The absence of wireless charging in Zenfone 2 is a deal breaker for me ( don't judge) and as soon as an appropriate case is available, I'll get it and the phone as well.
Please post your findings here.
Would love to use wireless charging but using a cover like the one posted is out of question.
I love the slim form and feel of this phone. so i will have to live without QI and other solutions.
This will occupy the mUSB port but would probably be the best current solution.
hkdmjack said:
This will occupy the mUSB port but would probably be the best current solution.
Click to expand...
Click to collapse
That's pretty cool. I like wireless charging because I'd rather not wear out my micro usb...but that setup kinda marries you to wireless charging all the time. I'd have to rig up wireless charging in the car and at work...not just at home. You use something like that?
nathan118 said:
That's pretty cool. I like wireless charging because I'd rather not wear out my micro usb...but that setup kinda marries you to wireless charging all the time. I'd have to rig up wireless charging in the car and at work...not just at home. You use something like that?
Click to expand...
Click to collapse
Not sure if I'm going to stick with the ZF2, so I haven't gone out and done all that yet but qi adapters are pretty cheap now for both home and car. How effective some of the car ones are though are another story. iOttie has two models out now that look promising for the car.
There may also be the possibility of placing those adapters into a separate case just meant for wireless charging... remove the case if you need the mUSB port.]
Or... if they do release new back covers... get one that you install the qi adapter in and then one that you won't have the qi adapter in.
WHYYYYYYYYY
Why did Asus decide not to include the qi pins in the back ((((((((((((((((((((((((((((((((((((((((((((
>_<
what to do :'(
Here's a teardown: http://www.myfixguide.com/manual/asus-zenfone-2-teardown/
You could solder the DigiYes posted earlier (http://www.amazon.com/gp/product/B00HI8JYFE) onto the usb board. Or you could probably just jam the wires into the connector for a non-permanent solution. The pictures of the DigiYes are a little conflicting, but if it does have leads for the data pins, you'd be best off omitting them (you'll be limited to 500ma qi charging).
This is of course assuming there's enough space to wedge the DigiYes between the back cover and phone.
ziddey said:
Here's a teardown: http://www.myfixguide.com/manual/asus-zenfone-2-teardown/
You could solder the DigiYes posted earlier (http://www.amazon.com/gp/product/B00HI8JYFE) onto the usb board. Or you could probably just jam the wires into the connector for a non-permanent solution. The pictures of the DigiYes are a little conflicting, but if it does have leads for the data pins, you'd be best off omitting them (you'll be limited to 500ma qi charging).
This is of course assuming there's enough space to wedge the DigiYes between the back cover and phone.
Click to expand...
Click to collapse
Which goes back to my point. Why did Asus purposdely omit to include QI/wireless charging pins on the back? It would had cost them hardly anything extra at all, and users could just have changed back cover to get wireless charging...
That one http://www.amazon.com/BLUBOON-Unive...2630&sr=8-2&keywords=qi+wireless+charger+1000 is 1000mA, if it does make a difference. But a case integrated receiver would be much better solution, if ever.
olegy said:
That one http://www.amazon.com/BLUBOON-Unive...2630&sr=8-2&keywords=qi+wireless+charger+1000 is 1000mA, if it does make a difference. But a case integrated receiver would be much better solution, if ever.
Click to expand...
Click to collapse
I bought that model. I have a Qi charger (used with a Nexus 5) hooked up to a 2A USB Adapter, and it barely charges the Zenfone. I do not recommend. Maybe a 2A receiver would work better.
It's ridiculous.... why did asus decide not to offer a wireless charging solution similar to the previous samsung galaxies/lg.
Have the pins for charging on the back, and let the user change the case to a qi receiver case or add a qi receiver pad inside. this is honestly the only thing that disappoints on this phone (((((((((((((
ziddey said:
Here's a teardown: http://www.myfixguide.com/manual/asus-zenfone-2-teardown/
You could solder the DigiYes posted earlier (http://www.amazon.com/gp/product/B00HI8JYFE) onto the usb board. Or you could probably just jam the wires into the connector for a non-permanent solution. The pictures of the DigiYes are a little conflicting, but if it does have leads for the data pins, you'd be best off omitting them (you'll be limited to 500ma qi charging).
This is of course assuming there's enough space to wedge the DigiYes between the back cover and phone.
Click to expand...
Click to collapse
I just received mine and there is enough space in the back cover for the receiver to fit in, albeit with a small bulge. It does show my phone as charging even when just held up to my Moto 360 cradle; whether or not it's charging, however, I have no idea.
raynan said:
I just received mine and there is enough space in the back cover for the receiver to fit in, albeit with a small bulge. It does show my phone as charging even when just held up to my Moto 360 cradle; whether or not it's charging, however, I have no idea.
Click to expand...
Click to collapse
Thanks for trying. Did you actually solder or just plug it in the usb port? If you plugged it in the usb port, does the cover close without damaging the cable?
I'm asking because if that works, we could potentially design a slightly thicker but hollow back case that could hold NFC and the wireless receive without unnatural bulges.
ameel said:
Thanks for trying. Did you actually solder or just plug it in the usb port? If you plugged it in the usb port, does the cover close without damaging the cable?
I'm asking because if that works, we could potentially design a slightly thicker but hollow back case that could hold NFC and the wireless receive without unnatural bulges.
Click to expand...
Click to collapse
It closes fine but there is a bulge and the cover is left slightly open.
Here's my solution. Doesn't look good but functional.
don't judge
Click to expand...
Click to collapse
Yeah I judge, wireless charging its just another feature. A small battery, a slow processor or low memory now that's a real deal-breaker since your phone wont last a day, apps will run like hell and you will always have to micromanage just for things to run properly.
I'm way more pissed off at this phone not having a removable battery, not just because its a real deal-breaker during travel where I will be forced to lug around one of those brickish power banks but because Li-ION batteries have the lifespan of a mosquito. I already had 2 phones like that and the result was always a massive pain in the ass to deal with.
I rather buy a case with an extra battery than this thing
Three pins USB Board?
Hi there
Maybe some one knows, what are those three pins on the USB board, that are accessible without disassembly phone?? That should be connectors to charging instead of usb socket?
I have a qi charger built into my car. I do not like aftermarket charger added to the phone. So this is a deal breaker for me and will not consider any phones without buildin qi charger.
Looking to buy this phone and own a quick charging card like this. Is it possible to slip the card under the back cover (without a case) or will it cause it to bulge in too unsightly a manner?
dud89 said:
It closes fine but there is a bulge and the cover is left slightly open.
Here's my solution. Doesn't look good but functional.
Click to expand...
Click to collapse
Slooop said:
Looking to buy this phone and own a quick charging card like this. Is it possible to slip the card under the back cover (without a case) or will it cause it to bulge in too unsightly a manner?
Click to expand...
Click to collapse
It can but causes a gap near the usb port that I could not close. I would've run it inside if it didn't do that.
dud89 said:
It closes fine but there is a bulge and the cover is left slightly open.
Here's my solution. Doesn't look good but functional.
Click to expand...
Click to collapse
Great Idea.
The speed of charge is 350 MAH ?? Is to slowly (USB PC charge normally 550 MAH)
Okay... i´m trying to make a mod for my Z1C to make it qi compatible....
I have the magnetic connector from a dock (which is broken).
So, using the connector + cover + glue can make it work.... and of course, need to solder the receiver to the connector....
But, the big question... which receiver should i use?
First of all, i´m from Argentina... so i have a limited access to receivers.
I´ve seen here receivers from Samsung Galaxy S3, S4, S5, Note III and Note 4, and a few others generic...
The maximum current that could find was 650mA... but read some comments that the output 1000mA is a lie... and there is no difference between the receivers...
So, which one should i buy?
Thanks to all!!
Finally, get a 700mAh receiver, and cutting out the cable, mixing + soldering + glueing it all together, and now it´s working....
Samsung GS4 1000mA QI receiver
I have a few Galaxy S4(1000mA)/S3(800mA) QI receiver cards.
The cards are different depending on the contact points location in the phones.
So you just soldered the internal magnetic charging points to a QI receiver card inside the phone?????
If you have the QI Receiver inside the phone (only real place for it), how much pressure does that place on the back cover??
The back cover tends to break away from the frame without much effort, so having the raised 'bulk' of a Qi card in the phone would only add to the pressure for the back cover to separate.
On Samsung phones (GS4 which I've added QI cards) it does take a bit of brute force to chip the back cover on again and some GS4 aftermarket cases/covers can not be used with the QI card installed due to the back of the phone being ever so slightly raised.
I have the QI receiver cards, glue seals rings for Z1C back cover and the Qi chargers and it is something I have thought about, but with three working magnet DK32 docks around the house, it's not something I have advanced at this time.
Well done for getting it to charge via QI charger if that is what you've done.
Maybe a photo would be nice.
Okay... now, the photos:
The tape is over the receiver module.
The original contacts from the receiver were removed, and over there, was soldered some copper tape (that can be seen in the photos).
The contacts were made by opening-cutting a magnetic cable, soldering it to the copper tape, and then glueing it to the cover, to maintain position.
The charger seems to be very picky about position. Searching over the internet, seems to be a common issue with this model...
Hope it´s usefull...
Well... about the charger, there seems to be an easy fix to it's pickiness... Take off the upper side... That way, the thing will gone a cool itself, and the connection will become a lot easier...
Hello everyone! How are y'all doing on this lovely week? I'm doing great!
I got my Zenfone 2 last week and I'm loving it, but I miss the hability to wireless charge it and especially to put it in the Air dock when I'm my car. So here I came asking for your aid!
Is there any dock like the Air dock for the Zenfone 2? I have an Air dock (1st Gen) that I bought back when I had a Gnote2 and because of the curved back and some wearing of the rubber in the dock the Zenfone 2 doesn't hold very nicely, so I'm thinking about making my own magnetic dock to put in the car.
Also, is there any way to get Qi wireless charging to work on it?
My initial idea on the magnetic dock won't even consider charging wirelessly since I plug it via a cable when on the car to listen to music/podcasts but maybe If I could get it to work, as times goes on, I would find a way to charge it wireless and get some sort of bluetooth dongle for the car.
My thoughts on a project for the dock involves using HDD magnets since they are really strong and it would make the device secure. But my concerns are if it's safe to use magnets that powerful near a phone for it's hardware and for it's battery, since s not easily replaceable.
Anyone here ever did or saw some sort of project like this? I'm possibly gutting my Air dock if the Zenfone doesn't support Qi wireless.
Any input is helpful, I'm completely open to suggestions!
There is an existing thread about QI solutions since there are no contact pins for wireless charging without some heavy modding of the device casing or usage of the USB port. As far as I'm aware, magnets have virtually no effect on the hardware except for a few sensors like the magnetometer and possibly the magnetic cover sensor.
raynan said:
There is an existing thread about QI solutions since there are no contact pins for wireless charging without some heavy modding of the device casing or usage of the USB port. As far as I'm aware, magnets have virtually no effect on the hardware except for a few sensors like the magnetometer and possibly the magnetic cover sensor.
Click to expand...
Click to collapse
Thanks! I'll try to find some weaker magnets to keep it in place without such a load in my mind, thank you for your help
Sure, good luck and I'd be interested in seeing what you think up.
I'd opt to use a cradle or similar holder instead of magnets. A strong enough magnet would probably add too much bulk. When looking for qi receivers, make sure to get one that has data pins (which will most likely be shorted to allow rapid charging). This one is still a reasonable price http://www.amazon.com/gp/product/B00WKWWMAM and fits well enough in most cases. It does even fit alright inside the back cover, but you're better off putting it between the phone and case. It'd make more sense to go qi all around since it becomes a hassle to unplug it..
If anything, you could save a bit of bulk by ripping it apart and removing the magnet. It does seem to severely cripple nfc though.
As for bluetooth receivers, they have become significantly cheaper recently. You could get an old bt2.1 a2dp button-less one and hide it away somewhere. I got one for $3 shipped. There are apps that can be set to auto-play on pair. For $10-15 more, you should be able to find something with buttons (back/playpause/next) and aptx support. Usually these will have a microphone as well